Invention and use of topical applications to treat common fungal diseases such as tinea pedis and tinea cruris, more commonly known as athlete's foot and jock itch, is known to the public. The active ingredient in these preparations is generally an anti-fungal agent such as miconazole, clotrimazole, grisefulvin or tolnaftate, although some preparations instead utilize an antibiotic, such as Nystatin (TM). In addition to these anti-fungal agents, some preparations also include an anti-inflammatory agent, such as a strong steroid. However, all of these prior anti-fungal preparations have several inherent problems or side effects that decrease their effectiveness.
Currently, the most widely used topical anti-fungal preparations are Tinactin (TM) and Micatin (TM). The anti-fungal agent used in Tinactin (TM) is tolnaftate, and the agent in Micatin (TM) is miconizole. According to a double-blind study comparing the superiority of a combination anti-fungal (clotrimazole/steroidal (betamethasone dipropionate)) product Cutis 30 (2):258 by M. Y. Wortzel, H1, since relatively few side effects are associated with these products, both are available over-the-counter, and therefore very popular. But despite their popularity, the use of such anti-fungal preparations have weaknesses. The main problem associated with these preparations is that they are unable to curb the redness and itchiness that are typically associated with the fungal infection. If the pain and itch of a lesion is not lessened, a patient is likely to scratch the infected area and spread the infection. Thus, when using these anti-fungal preparations the lesions often increase in size and spread to other areas via auto infection.
To remedy the problem of inflammation and auto infection, several anti-fungal applications are available that not only include an anti-fungal agent, but also an anti-inflammatory agent. U.S. Pat. Nos. 5,219,877 to Shah et al., 5,110,809 to Wang et al. and 5,310,545 to Eisen all indicate that a combination of an anti-fungal agent and a corticosteroid anti-inflammatory agent can effectively treat fungal infections and decrease the inflammation of the infected area. Commercial products available of this type include Lotrisone (TM) and Mycolog (TM). Lotrisone (TM) contains 1% of the anti-fungal agent clotrimazole and 0.05% of the anti-inflammatory agent betamethasone dipropionate. Mycolog (TM) employs Nystatin as its acting anti-fungal, and triamcinalone as its anti-inflammatory agent. The introduction of these strong steroids into anti-fungal applications allows the anti-fungal agent to combat a fungal infection, while the steroid combats the inflammation and irritation caused by the infection.
However, these compounds have not been very successful because they have several inherent weaknesses which limit them to use only by prescription. First of all, the addition of anti-inflammatory steroids to skin preparations is not an obvious decision, as the steroid's molecular structure can cause the anti-fungal or antibiotic to become deactivated, and thus much less effective. In fact, steroids actually increase the spread of viral diseases. In addition, as W. F. Barkey points out in Striae and persistent tinea corporis related to prolonged use of betamethasome dipropionate 0.05% cream/clotrimazole 1% cream in the treatment of tinea cruris and tinea corporis in J AM Dermatol 1988;18:17:518-0, potent, concentrated forms of corticosteroids have several toxic side effects such as skin atrophy, rebound phenomenon and suppression of the adrenal cortex. Both nyastin and clotrimazole are also liver toxic. Therefore, while the addition of corticosteroids helps decrease fungal inflammation, it also decreases the effectiveness of the total preparation and creates other undesirable side effects.
To improve upon these preparations, the newest generation of antifungals are the allyl-amine non-steroidals such as Terbinafine and Naftifine. E. G. Evans et al. find in a comparison of tertinafine and clotrimazole in treating tinea pedis, Bmj 1993 (690):645-7 that these non-steroidal antifungal compounds work effectively and may also contain anti-inflammatory properties without using steroids. However, these compounds have also proven to have toxic side effects and are therefore only available with a physician's prescription and not widely used.
Thus there is a clear need for an anti-fungal preparation that can quickly combat a fungal infection, control inflammation and increase absoption without producing harmful side effects to the user. Thus, the new invention provides a combination of ingredients o that offers all of the advantages and none of the disadvantages of the prior art, thus allowing for improved treatment of common fungal infections. The present invention fulfills these needs and provides further related advantages.